Automatic signal and train-control system.



PATENTED JULY 4:, 1905.

I-L M. DAVENPORT AUTOMATIC SIGNAL AND TRAIN CONTROL SYSTEM.

APPLICATION FILED SEPT. 8, 1904v l0 SHEETS-SHBET 1.

No. 793,827. PATEN'IED JULY 4, 1905. H. M. DAVENPORT.

AU'TQMATIU SIGNAL AND TRAIN CONTROL SYSTEM" APPLIUATIOE FILED $EPT. 8,1904.

10 SHEETS-SHEET 2.

No. 793.827. PATENTED JULY 4, 1905 H. M. DAVENPORT AUTUMATIU SIGNAL ANDTRAIN CONTROL SYSTEM.

APPLICATION FILED SEPT. a, 1904.

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PATENTED JULY 4, 1905 APPLIOATIOH FILED EEPT.8,1904.

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W PW m w m PATENTED JULY 4-, 1905.

H. M, DAVENPORT. AUTOMATIC SIGNAL AND TRAIN CONTROL FSYSTEM.

APPLICATION FILED SEPT. 8. 1904.

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PATBNTED JULY 4, 1905.

H. M DAVENPORT. AUTOMATIG SIGNAL AND TRAIN CONTROL SYSTEM.

APPLIOATION FILED SEPT. 13, 1904.

10 SHEETS-SHEET 7 No. 793327. Y PATENTED JULY 4;, 1905.

HI. DAVENPORT AUTOMATIC SIGNAL AME TRAIN CONTROL SYSTEM.

APPLIUATIOIT FILED QEPT. B, 19%.

IOEHEETW-SHBET 8.

['wewf PATENTED JULY 4-, 1905.

H. M. DAVENPORT. AUTOMATIC SIGNAL AND TRAIN GONTROL EsYfiTE'M.

APPLIUATION FILED EEPT. 8, 1904:.

10 SHEETS-SHEET 0.

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PATENTBD JULY 4, 1905.

H. M. DAVENPORT.

APPLICATION FILED SEPT s. 1904.

AUTOMATIC MGNAL AND TRAIN CONTROL SYSTEM.

ED S AES Patented July t, 1905.

PATENT Oriana HENRY M. DAVICWIOR'I, OF LONGBIGAOII, CALIFORNIA,ASSIONOLI TO Ah IERIOAN SVVITUII AND SIGNAL (JOivIPANY, Oi LOSANOICLICS, CALIFORNIA, A CORPORA'IION OF ARIZONA TITERH'IIORY.

MUTUIVIATIU QIONAI. AND TWAIN OQNIWIUL SYSTEM SPECIFICATION forming partoi Letters Patent No. 798327, dated July t, 1905.

Application filed September 8, 1904:. Serial No, 223.755.

10 Ml who/1t it may concern:

Be it known that 1, Manny M. DAVENPOI-t'l, a citizen of the UnitedStates, residing at Longbeach, in the county of Los Angeles and tttatcof California, have invented a new and useful Automatic Signal and'Ilrain-Control System, of which the following is a specification.

This invention rclatesto a system for automatically operating signals onrailways and on trains to avoid accidents and also for automaticallycontrolling trains in such a manner as to absolutely prevent accidentsif the signals given by the system are not acted upon by those havingthe trains in charge.

It relates 'iartieularly to a system such as described which operatesentirely automatically, not requiring the cooperation of human agency.

It is a block system, but diIIers from the ordinary block-system type inthat the blocks are progressive and travel with the train that is tosay, the railway or that part of it which is embraced by the system isprovided with devices arranged at suitable intervals which are broughtinto action as a train moves along. When a train is at any point, adeiinite number of these devices forming a chain of units adjacent thetrain are active. As the train progresses consecutive devices at thefront are sequentially brought into the chain of active units and theactive devices as they serve their turn are sequentially dropped fromthe rear of the chain and left in inactive condition. Thus a train atany point of the tom lies within a chain of active devices forming aprotective zone, and the zone travels with the train. Only those devicesembraced in a zone related to a train are active, and every train on theroad is hedged by its protective zone of devices, all other devices onthe road intermediate 01 the active train zones being .inactive.

The system is such that a train cannot tres pass within the protectivezone of another train without being automatically signaled. When a traintouches the zone of another train, a warning-signal is given to one orboth of the trains, which indicates that the trains areas close togetheras safety will permit. If the trains are both going in the samedirection, this signal is given to the rear train only. If the trainsare approaching each other, the signal is given to both trains. If thiswarning-signal is not acted upon and the trains are allowed to drawcloser together, one or both trains are automatically brought to a stop.If

the trains are both going in the same direction, the rear train isbrought to a stop, while if the trains are approaching each other fromopposite directions both trains are brought to a stop.

The construction of the system in such that the protective zone for atrain may have any suitable limits in front of or behind a train.

The system is applicable to strmm-railways, electric railways, and otherrailways, and in the present embodiment does not depend for itsoperation upon electric or pneumatic devices. In the present embodimenteach unit is a positively-operating mechanism, the units aremechanically connected, and the power for operatil'ig a chain of unitsis derived bodily and positively from the train or car. Certain of theunits in the zone when rendered pro tective are adapted to operatesignals of any kind whether mounted locally along the railway or carriedon the train---such as whistles, bells, semaphores, or the like and tooperate devices for automatically controlling a train, such as air-brakevalves for setting brakes of a train, or electric switches forcontrolling the circuit through a car of electric systems, or tooperateapparatus locally situated along the railway, such astrack-switches, crossinggates, etc.

The object of the invention is to perform these functions and otherminor functions by a construction which is simple, positive in action,durable in use, and economical of construction and maintenance.

The z'tccom tianying drawings illustrate the invention.

Referring to the drawings, Figure l is a side elevation of one of theunits, a part of the track-lever being broken away. Fig. 2 is anelevation of the reverse side from that shown I in Fig. 1. Fig. 3 is aforward end elevation, parts being in section on line X X Fig. 2. Fig.4. is a plan view with the track-lever removed. Fig. 5 is part of an endelevation looking at the left end of the machine as shown in Fig. 1.Fig. 6 is a side elevation illustrating the track-lever and adjacentparts, the track-lever being up. Fig. 7 is a view similar to Fig. 6 withthe track-lever down. Fig. 8 is a sectional view on line X K, Fig. 7.Fig. 9 is a section on line XX, Fig. 6. Fig. 10 is a perspective view ofthe ratchet-lever. Fig. 11 is a perspective view of one of the arms ofthe ratchet-lever. Fig. 12 is a perspective view of the dog for theoperatingratchet. Fig. 13 is aperspective view of a removable strap forthe ratchet-lever. Fig. 14 is a side elevation of a cable-terminal andadjacent connections. Fig. 15 is a perspective of the locking-bolt. Fig.16 is a side elevation of the signaling and controlling devices of a carabout to be operated by passing over a trip-lever. Dotted lines showother positions of the controlling and signaling devices. Fig. 17 is aside elevation of tripping-levers cooperating with a switch. Fig. 18 isa diagrammatical view showing a series of units and illustrates thebalancing of the cables. The units are shown in normal position. Fourunits are removed from the intermediate part of the chain to economizespace. Fig. 19 is aview similar to Fig. 18, showing the forward strokeof the coupled cables and connected units. Fig. 20 is a view similar toFig. 18, showing the chain of coupled cables and connected cablesshifted back and illustrates the zone as having progressed one pointahead. Fig. 21 is a diagrammatical view, the upper section representingunits and cables in side elevation. The lower section represents thetrack in plan and the two independent sets of units and representsconditions of trippinglevers and track-levers relative to the positionof the train. Fig. 22 is aview similar to Fig. 21, representing thecondition of tripping-levers and track-levers in the forward stroke ofthe chain of cables and units as actuated by the train. Fig. 23 is aview similar to Fig. 21, representing the conditions after the returnstroke from the position shown in Fig. 22. Fig. 24 is a perspective viewof a portion of the. forward coupling-bar. Fig. 25 is a perspective viewof a portion of the rear coupling-bar. Fig. 26 is a diagrammatic planview of a switch-protecting system with the switch represented closed.Fig. 27 is a view similar to Fig. 26 with the switch open. Fig. 28 is aplan view of what is shown in Fig. 7. Fig. 29 is a perspective of thelocking-dog for the rear coupling-bar. Fig. 30 is a view, partly insection, on line 1. :0 Fig. 4;, showing a portion of parts adjacent thelockingdog for the rear coupling-bar and illustrates the dog out ofengagement with therear locking-bar. Fig. 31 is a view similar to Fig.30,

1 showing the dog about to spring into the notch in the rearcoupling-bar.

The system comprises units distributed along the railway, with suitableconnections for securing harmonious action of the units. Cars operatingover the system are equipped with signaling or controlling apparatus, orboth, which are adapted to be operated by the units when brought intocontact therewith. Each unit has several primary conditions. It may beconsidered inactive when out of a chain and active when in a chain. henactive, each unit may be considered protective or non-protective,according as it presents or retires a tripping device for signaling orcontrolling a train. As an active intermediary in a chain a unitoperates the chain or series of units when the unit is directly actuatedby the train its block is protecting, and a unit connects itself with aseries of units to maintain progression of the Zone as the traintravels, and the unit disconnects or detaches itself from the seriesafter having performed its duty in the chain. In the present embodimenteach train-block embraces ten of these units. Each unit when exercisingin a block performs a cycle of ten points. The ten respective units of ablock are coupled in a series, and although the respective units performsimultaneously each unit performs a different point. Thus while the twoextreme units of a block are simultaneously performing points Nos. 1 and10 the respective intermediate units are performing their relativerespective intermediate points according to their relative location.

A clear aspect of the principle of the progressive movement of a blockis to consider the present specific embodiment of the chain, whichconsists of nine coupled cables forming a block. This chain of cables isgiven a forward and backward shift lengthwise a few inches when thetrainpasses over one of the units connected to the chain. If the unitsare arranged at intervals of one thousand feet, the actuation of thechain of cables takes place once in every thousand feet of travel of thetrain. In Fig. 21 the train is shown at a point between units 6 and 7.hen the train passes over unit 7, the chain of nine coupled cables 3, 4,5, 6, '7 8", 9 1.0", and 11 is shifted forward and back, coupling withcable 12, thus bringing a fresh link into the chain at the front, andthe cable 3 is uncoupled from the rear end of the chain, thus forming anew chain of the same length of nine cables as the old chain, but lyingone point farther ahead on the track. The train is now between units 7and 8. (See Fig. 23.)

Then the train has traversed the distance between units 7 and 8 andpasses over the unit 8, the new chain of cables 4, 5, 6 7, 8 9, 10, 11,and 12 is shifted forward and back and coupled with cable 13, thusbringing a tresh link into the chain, and the cable at is uncoiuiiledand another new chain of nine cables is formed which lies two pointsahead of the lirstu'ientioned chain. The train now lies between units 8and 9. Thus there is a progressive filOVOITlOlllJ. ol the protectiveblock which accompanies the train.

in the present Lli'llJOdililGXll; each unit at certain points in itscycle projects a tripping device, which will cooperate withtrain-giilard- :ing' devices, such as warning and controlling devices,on trains which are encroaching on the block. In this embodiment the twotoremost and two rearmost units of a train-block present each a tri iiing device. Thus while the train is between units 6 and 7 units 3 andat at the rear and units 10 and ll at the front present tripping devi llhen the train passes over unit 7 in the formation oi the new block,trippii'ig devices ol units 5 and 12 are projected and tripping devicesof units 3 and 10 are retired,tripping devices of unitssland l lbeingmaintained. l Vhen the train passes over unit 8 to form the nextnew block, the tripping devices of units t3 and 13 are projected and thetripping devices of units at and ll are retired, the tripping devices ofunits 5 and 12 being maintained.

Under the present construction only one unit at a time, and that onebeing always the unit nearest ahead of the train, is adapted to beoperated by the passing over it ol the train to actuate the chain ofcables in the block. Thus whenever a chain of cables is actuated oneunit connected to the chain is operated one point of its cycle bymovement imparted to it directly by the train, while all the other unitsconnected with the chain are operated indirectly through the medium olthe shi ltine chain of cables, each operating its respective point inits cycli according to its relative location in the chain.

ltach unit has a track-lever which actuatcs the mechanism of the unitwhen the lever is depressed by the train. The constructionaniiloperation of the cycles of the units in a block are such that thetraclelever oi the unit just ahead of the train always up and all othertrack-levers are down. Thus as the train passes over track-lever of unit7 that tracklever is depressed and the traclclever of unit 8 is raised.hen the train passes over unit 8., its traclvlever is thereby depressedand track-lever of unit 9 is raised, and so on.

in the present embodiment a double set of units is employed, each havingits cables. The two sets are inde 'icndent of each other; but the unitsare preferably arranged in pairs, as indicated in the diagrams of Figs.21, 22, and 23, one set, as the set having units 1 to 15, being operatedby trains going in the direction indicated, the other set having units lto 15, being operated by trains running in the opposite direction; butthough the sets are inde- IFS.

pendent and are operated independently the tripping devices projected byeither set are el'lective l'or c u ieratine' with the signaling andcontrolling devices on trains which are running in either direction.Thus the trip ping device ol unit 11 as projected in :llig. it will warna train approaching from the opposite direct-ion from that ol the movingtrain shown, and the trippii'ig device ol unit 3 will warn a trainfollowing the train shown. it in either case the warning is not actedupon, then in the lirst case the tripping device of unit 10 will stopthe train approachiitc headon, and in the second case the trippingdevice of unit st will stop the train approaching at the rear. in the lori'ner case with both trains approaching head-on not only one train iswarned and stopped, but both trains are warned and stiu'iped. Thusreferring to Fig. 21, assruning that a train not shown is approachingthe one shown and lies between units 12 and 11, this assumed train willhave projected tripping devices oi units '7 and 8". Now when both trainsFurther approach the train shown will be warned by the tripping deviceol unit'T, while the assumed train will be warned by the tripping deviceol unit ll. 11'' both trains still proceed regardless of the warnings,then the train shown will be absolutely stopped by the tripping deviceol unit 8 and the assumed train will be absolutely stopped by thetripping device of unit 10.

Obviously in the case of the assumed rear train following the trainshown only the rear train will be warned and stopped, as the rear traincannot n'oject tri iping devices .inthe block covering the train shown,as the cable 2 is micoupled from the cable 3, and while the rear traincan draw near to the block ol the front train the block oi the reartrain will gradually become shorter, as it cannot couple on cables atits front until the trout train leaves units at its rear at the propercyclepoint to permit coupling. Thus there is no interference with theproper working ol the system when a rear train approaches close to atrain ahead of it nor there any interli'ercnce when two trains approachhead-on, as in that case the two sets are independently operated.

Having described the general nature ol the systen'i and some speciliecharacteristics of the lJl'CSGl'llJ embodiment by which the system maybe carried out, one form in which a unit may be constructed will now bedescribed.

Each unit is preferably incased in an iron box 20, which is m'el crablysunk in the earth close to the track-rail, as shown in Fig. 8.

21 designates a base having standards .22. A main shaft is mounted inthe standards 22, and rigidly mounted on the shaft 23 is a ratchet 52-1.

25 is a ratchet-lever having a loi'ig haltround hub 26 mounted to rockon the shaft 23, being retained thereon by a strap 27. 25%

'bears against the pull-rod 10 and holds the is a rock-lever alsoloosely mounted on the I shaft 23 and lying parallel with theratchetlever 25, the two levers being fastened together at their freeend by a pin 29, the ratchet 24 being positioned between the two levers25 and 28. A sliding dog for actuatlng the ratchet 2a is mounted betweenthe two lovers 25 and 28, being provided with slotted wings 31, throughwhich the pin 29 passes, the dog further being held in place by upperand lower plates 32 and 33, fastened to the levers 25 and 28. The twolevers 25 and 28 form practically one lever, which will hereinafter bereferred to as a ratchet-lever.

A shaft 34 is mounted on the standards 22, and loosely mounted on theshaft 3% is a rocklever 35, one end of which is connected by a link 36with the pin 29. A fiat spring 37 is attached to the link 36, the freeend of the spring bearing against the slotted wings 31 of the dog 30 andserves to hold the dog yieldingly against the ratchet 2st, the slottedwings 31 serving to limit the play of the dog when actuated. One of thestandards 22 is provided with a vertical bearing 38, and the base 21 isprovided with a socket-bearing 39, while a pull-rod 1O is mounted inbearings 38 and 39, being vertically movable therein. Pivoted to therock-lever is a double catchlever 41, comprising two plates havinghooked ends 12, and forming a forked hook which straddles the pull-roda0 and which normally engages studs 13 on the pull-rod. The catchlever4:1 is bridged with a cross-pin ate. which catchlever in position, therebeing a flat spring 15 for normally holding the catch lever with the pin-14: resting against the pull rod 10.

A leaf-spring 180 presses against the under side of the rock-lever 35and serves to normally hold the ratchet-lever and connected elements inthe position shown in Figs. 1 and 2. A retaining-ratchet -16 is rigidlymounted on the shaft 23, while a spring-pressed retaining-pawl a7 isslidably mounted in a socket 18 on a standard 22. Referring now to Fig.6, a track-plate :9, which is outside the box 20, is fastened to theadjacent track-rail 50, and one end of a track-lever rock-shaft 51 ismounted in the track-plate 4:9. The rockshaft 51 extends into the box 26and carries an arm 52, which is forked to receive the upper end of thepull-rod 4:0, being connected therewith by a bolt 53, having a slot 5%to permit of the necessary swinging movement of the arm. The shaft 51also has another arm 55, which lies near the track-plate 4:9 and whichis connected by a link 56 with a tracklever 57, the track-lever 57 beingpivoted at 58 to the track-plate a9. The track-lever 57 is offset, so asto present its upper inclined bearing edge 59 at the top face of thetrackrail 50. The track-lever 57 is adapted to be pressed up into theposition shown in Fig. 6

by means of a Hat spring 60, there being a slotted bracket 61 forengaging a toe 62 on the track-lever to limit the upward position of thetrack-lever.

63 is astud mounted on the track-plate 19, while the track-lever 57 isprovided with a stud 64c, to which studs a pair of toggle-links 65 arepivoted. A stub-shaft 66 is mounted on the track-plate 19 and carries acam-linger 67.

\Vhen the track-lever 57 is depressed, it rocks the shaft 51 and throughthe medium of the arm 52 elevates the pull-rod 4:0, which through themedium of the catch-lever 11, rock-lever 35, and link 36 pulls down theratchet-lever, thereby advancing the ratchet 2st one tooth, theretaining-pawl 457 clicking into the next notch in the retaining-ratchet4:6 and preventing rearward movement of the ratchet 2a. As the pull-rodil) goes up the pin 4% of the catch-lever 4L1 strikes an inclinedabutment il, and the catch-lever is thereby shunted out of engagementwith the pull-rod, allowing spring 180 to restore ratchet-lever 25, rockarm 35, and pulling down catch-lever 411, the pin as riding down alongthe side of the pull-rod. The pull-rod is thus left elevated when thetrack-lever is down, as shown in Fig. 7. The track-lever does notimmediately rise, being held down during several steps in the cycle,after which it is released, as will be described later, and when thetracklever is released the pull-rod descends and the studs 4L3 ride overthe rounded nose of the catch-leverll and are caught under the hook 12as the catchlever snaps back. One side of the retaining-pawl a7 has aneasy inclination, and the notches in the ratchet 16 are correspondinglyformed, so that no great impedance is given to the ratchet 16 while itis being turned. hen the lever 57 is depressed, it straightens thetoggle-links 65, as shown in Fig. '7, so that the track-lever 57 isprevented from rising. The track-lever 57 is raised at a certain pointin the cycle of the unit by the toggle-links 65 being flexed outwardlyby the rocking'of the cam-linger 67, as will be hereinafter explained.

Mounted on the standards 22 are ways 68 and 69. (See especially Fig. 1.)The ways 68 and 69 are provided with channels in which coupling-bars 70and '71 are slidably mounted. The coupling-bar '70 extends rearwardlyfrom i the machine,while the coupling-bar 71 extends forwardly from themachine, the two bars overlap iiing, as shown in Fig. i. The hub 26 ofthe ratchet-lever 25 has a block 72, which is provided with notches 73and 7a. The rear coupling-bar '70 passes through the notch 7st and theforward coupling bar 71 passes through the notch '73. provided with aslot 7 5, in which is pivoted a locking-dog '76, adapted to be pressedout by a spring 76, and the rear couplingbar 70 has a notch 76", whichnormally receives the The block 72 is also beveled head, as shown,contacting with the "mass? lockingdog 76, Fig. 8. The ratchet 241 has apocket 24, in which is a plunger 24-", having an inclined face 2 1. Acompression-spring 2 1, which is much stronger than the spring 76,serves to yieldingly hold the plunger 21" flush with the side face ofthe ratchet 24, as shown in Fig. 30. The length of the spring 2 1" isnot great enough to cause the plunger to protrude from the pocket at anytime. The forward coupling-bar 71 is provided on its under side with anotch 77, (see Fig. 24,) and the under face of the forward coupling-bar71 is slightly eoncaved, as at 78, adjacent the notch 77. The block 72is also recessed laterally to form way for a locking-bolt 7 9, which isslidable therein and which has side lugs 80, slidable in ways 81. (SeeFigs. 3 and 10.) The lower end of the locking-bolt 79 has an inclinedface 82, while the upper end of the locking-bolt 79 has a rounded tip83. Projecting up from each lug 80 is a pin 8st, suitable plates beingscrewed to the top of the block 72 and perforated to receive the pins 84to form guides therefor, while compression-springs 86 encircle the pins81, being interposed between the plates 85 and the lugs 80. Screwed tothe side of the block 72 is a thimble 87. Slidably mounted within thethimble 87 is a releasing-bolt 88, having a inclined face of thelocking-bolt. The other end of the release-bolt has a rounded tip 89,the shank of the release-bolt having a collar 90, which l as a slidinglit in the thimble 87, and a compression-spring 91 is interposed between the collar and a stationary washer 92 in the inner end ofthethimble, the spring 91 serving to yieldingly press the tip 89 againstthe side face of a cam 93, which is rigidly mounted on the main shaft23. Another cam 91 is mounted on the shaft and is preferably formedintegral with the cam 98, there being a neck joining the two cams. Thecam 93 is provided with a recess 96, having a pocket 97, while aretractor-bolt98, having a beveled head, is slidably mounted in therecess 96. The stem 99 of the retractor-bolt extends loosely through theneck 95 and cam 91. as shown in Fig. 3, a compression-spring 100, lyingwithin the pocket 97 and bearing against the head 98, serving to pressthe head l outwardly, the outward movement of the rej tractor-bolt beinglimit-ed by a nut 10] on the I end of the stem 99. Another cam 102 isalso l mounted on the main shaft 23. Bell-crank i levers 103, 10-1, and105 lie, respectively, under and in alinement with the cams 93, 9 1, and102, each being loosely mounted on the shaft 3 1, the short arm of eachof said levers having an antifriction roller 106 for riding against itsrespective cam. Three vertical operating-rods 107, 108. and 109 arerespecl tively mounted over the ends of the long arms l of therespective bell-cranks 103, 104-, and

105, the lower end of each operating-rod havm at)" ing an antifrictionroller 110, which rests against its respective a rm. the opnrating-rods107, 108, and 109 being slidably mounted in upper guides 11.1 and lowerguides 112. The lower parts of the operating-rods 107, 108, and 109 aresquared, as shown, to slide in the guides 112 and prevent the rods fromturning.

The stub-shaft 60, before dcseri bed, extends into the box 20 andcarries a rigid arm 113, having a slotted end, which is connected withthe upper end of the operating-rod 109 by a bolt .1 1%.

Referring to Fig. 8, 115 designates an arm carried by a shaft 116, whichin this instance extends across the track underneath the trackrails 50,being journaled at one end in a hearing 1 17 and at the other end lieswithin a sleeve 118, which sleeve is mounted to rock in a hearing 119.(See Fig. 3.) The sleeve 118 also carries an arm 115", similar to thearm 115. A trip-lever shaft 120 is mounted in suitable journals 121underneath the track-rails 50 at some distance from the arms 115 and 115and near the lower end of the traclvlever 5'7. 'lrip-levers 116 and 116are loosely mounted on the shaft 120 and are respectively connected withthe arms 115 and 115" by connectingrods 122. The two trip-levers aresimilarly constructed, their upper ends being forked and carryingantifriction-rollers 128. The end of the shaft 116 which lies within thebox 20 projects beyond the sleeve 118 and carries a rigid arm 121,having a slotted end and being connected with the upper end of theoperating rod 107 by a bolt 125. The sleeve 118 carries a rigid. arm120, the end of which is forked and slotted and connected to the upperend of the operating-rml 108 by a bolt 127.

Both couplingbars 70 and 71 have rounded stems 128, which arescrew-threaded and carry spring-adjusting nuts 129. (See Fig. 14:.)

A coil tGllSlOl'l-SPl'lHg is attached to the adjustingnut on the stem ofthe eoimling-bar 70 and to the frame of the machine, while a similartension-spring 131 is attached to the adjusting-nut 129 on the stem ofthe couplingbar '71 and to the frameof the machine. Suitable cuppedsockets 132 are employed for housing and protecting the ends of thesprings and for holdii'ig the springs substantially concentric withtheir respective coupling-bar stems. The end of each stem 128 isconnected, by means of a swivel 133, with its cable. The two springs 13l and 15.11 are both equally stretched and evenly balance each otherwhen the ratchet-lever stands back in its normal position.

One form of signaling and controlling device which may be employed on acar is shown in Fig. 16. This apparatus may be mounted, preferably, onthe locomotive. designates the wheels on the locomotive. The train-pipe151 of the air-brake system is provided with a valve 152, having an arm153, while the signal-pipe 154 is provided. with a valve 155,

A rect action of the train or by being actuated through the medium ofother units. The position in the cycle which a unit has will bedesignated as position P, P P, P*, P P P P P and P as indicated on theratchet in Fig. 2. As the ratchet 24 operates the distance of one tooththe coupling-bars 70 and 71 are advanced as one piece and retracted; butwhile the unit is performing the ninth step the rear coupling-bar 70does not move, and while the unit is performing the tenth step in itscycle the forward coupling-bar 71 does notmove,thetwocoupling-barshavingrespectively during the eighth and ninth strokes beenuncoupled. P will be used to designate that position which the unit hasafter having performed the tenth step, with the two coupling-bars 70 and71 coupled. The first movement of a unit in its cycle of operation isfrom position P to position P and its last move- 'ment in the cycle isfrom position P to P.

The operation of a unit in going through its successive steps will firstbe described without considering its relation with other units. It willbe assumed that the unit stands in position P. \Vhile in this positionits tracklever is down and its trip-levers are down.

the valve-stem 156 carrying an arm 157. ratchet 158 is mounted on thevalve-stem 156, and the arm 157 carries a pawl 159 for actuating theratchet, and thereby the valve-stem. Fixed with the ratchet 158 is aplate 160, having an operating-finger 161. A bracket 162, forming a stopfor the ratchet-lever 157, may be attached to the signal pipe, as shown.hen the valve 155 is opened, a signal may be operated thereby such, forinstance, as the whistle 163, which is connected by a pipe 164 with thesign al-pipe 154:, the whistle being preferably located in the cab ofthe locomotive. The valvestem 152 may also have rigidly attached theretoa switch-blade 165. which normally bridges terminals 166 and 167 in anelectric circuit. The ratchet-lever 157 has a path of movement whichwhen the train is in motion will bring it against one or the other ofthe trip-levers 116 or 116", according to the direction of travel of thetrain, inasmuch as the ratchet-lever 157 is mounted at one side of thetrain.

In operating the train the two valves 152 and 155 are normally closed,as illustrated in Fig. 16; but if the ratchet-lever 157 should strike atrip-lever it will be moved into the position shown in dotted lines asit is drawn over the roller of the tripdever, which will open the valve155 and blow the whistle and move the operating-linger 161 into theposition shown in dotted lines, so that it is about in contact with thelever 153, the ratchet-lever 157 being returned by the spring to itsnormal position resting against the stop 162, but leaving theoperating-finger 161 in the position shown.

it advances the ratchet 2 1 one tooth and the main shaft, with cams,turns accordingly. During the forward movement of the ratchetlever thebars 70 and 71 shift forward, thereby stretching the spring 131 andgiving it a greater tension and relieving the tension of spring 130.During the return stroke as the coupling-bars 70 and 71 shift back thespring 131 is relieved in tension and the spring 130 is stretched sothat both springs are again under equal tension and balance each other.The spring 180, which has been flexed during the forward stroke of theratchet-lever, reacts and restores the ratchet-lever and connectedelements to normal position with the dog 30 in engagement with a newtooth of the ratchet. The unit now stands in position 1 The ratchet isagain advanced and the foregoing action is repeated. As the unit isoperated from position 1 to P during the forward stroke the cam 102presses down the rocklever105, elevating the operating-rod 109, rockingthe shaft 66, and thereby turning the cam-linger 67 against thetoggle-links (see Fig. 6) and flexing them, thereby allowing the spring60 to raise the track-lever 57. During this forward stroke the cam 102only momentarily engages the rock-lever 105 sufficiently to trip thetrack-lever, and the rocklever 105 and described connections arerestored by gravity to normal position, leaving the track-lever raised.The unit now stands in position P In its next step from posi- If thesignal is not acted upon and the train proceeds and strikes the nexttrip-lever, the ratchet-lever 157 will again be rocked into the positionshown in dotted lines as it rides over the trip-lever roller, which willadvance the operating-finger 161 still farther, and as theoperatingfinger bears against the lever 153 it will open the valve 152and set the brakes. At the same time the switch-blade 165 will be movedi clear of the terminals 166 and 167, thus breakl ing the circuit. Thetrain is thus automatically brought to a stop. This circuit-closingdevice may be employed to advantage on electric systems, but may bedispensed with on steam-roads.

The units are distributed along the track and in this embodiment areconnected by cables, the coupling-bar 70 of a unit being conl nected bya cable with the coupling-bar 71 of the unit behind. In order todescribe the operation, it is necessary to distinguish the differentsteps in the operation of each unit. Each unit when exercising in ablock per: forms all of the steps; but the respective units in a blockperform different steps at the tion P to P the unit is operated bydirect same time. Each step in the operation of a action of thetrack-lever, the latter being deunit is carried out whenever the ratchet24 of pressed by the train and operating the ratchetthat unit isadvanced one tooth either by dilever,

as before described, the track-lever belVhen the ratchet-lever 25 isrocked forward,

ing locked when depressed by the straightenreactivecontraction olthetension-spring .131.

big oi. the toggle-links and ing the remainder oi the cycle.

in the previous described ste s-namely, the third and fourth steps -theunit was op erated by the shifting of the coupling-bars and 71 and notby direct action oi its tracklever, as will be later described. As theunit operates from position 1 to P the ratchet is again advanced onetooth and the main shaft and cams turned accordingly. As the unit isoperated from position P to P during the forward stroke the cam 94Lpresses down the rock-lever 10st and elevates the operating-rod 108,rocking the sleeve 118, tilting the arm 1.15, and raising the trip-lever116". (See Fig. 7.) The unit now stands in position P its it is operatedfrom position P to l the cam 941-. still holds the rock-lever 10stdepressed and the trip-lever 116" up.

During the previous steps the dog 76 has kept in the notch 76', beingheld out by bearing against the side face of the ratchet 2 1; but duringthe back stroke of the ratchet-lever the dog 76 springs into the pocket27b and rests against the plunger 24,", Fig. 30, thereby uncou iling therear coupling-bar 70. The unit is now in position i. As the unitoperates from position P to 1"" the cam 94: moves oil" from therock-lever NM and the roek-lever1()-1- drops, the operating-rod 108 alsodropping by gravity, the sleeve 118 turning back accordingly, and thetrip-lever 116" thereby dropped. l )uring the back stroke in IHOVlIlQ'from P" to 1"" as the ratchet 52st holds still the dog 76 rides over theinclined face 24" ot' the plunger 2t", and as the dog cannot retract onaccount oi its rubbing along the smooth side face of the couplingbar 70it forces in the plunger 2%, compressing spring 24:; but as soon as theratchet-lever is fully retracted the dog 76 registers with the notch'76, Fig. 31, and snaps thereinto by the expansion of spring 2%, therebycoupling the rear cou 'iling-bar 70.

During the back stroke in operating from position l to P the pin 89drops into the pocket 96 and strikes against the retractorbolt 98, thereleasing-latch 88 being forced into the pocket by the spring 91. Theforward coupling-inn '71 upon thus being released is inn'nediatelyretracted by spring 131. The rear coupling-bar To is also retracted withthe ratchet-lever. The reason for the retraction oi the rearcoupling-bar T0 at this point in the cycle is not apparent until therelation of the unit to other units is considered, and topreventcontusion this will be treated later.

i'hen a unit stands in position P" the next function arisingin it willdepend upon whether the unit stands at the rear of the chain of units orat the Front 01 the chain. If it stands at the rear, the next movei'nentin it will be simply an out and back shift oi the forward coupling-bz'ir 71 and consequent expansion and remaining so duri All otherparts oi the unit are inactive and unal'l ected; but this function isnot here regarded as a step in the cycle and need not be consideredfurther at this point.

The next step in the cycle of the unit is in i'iniving from position11"" to P, and while making this step the unit lies at the head of thechain. The rear bar it) is relieved in tension, as will be treatedlater, and moves Forward with the ratchet-lever. During this forwardmovement the front coupling-bar remains stationary, being held back byspring 131. its the ratchet-lever moves forward it advances the ratchetone tooth, turning the main shaft and cams acii-ordingly. lt will beremmnbered that the locking-bolt T9 is disengaged from the notch 77 ofthe forward coupling-bar T1 and that the pin lies in the pocket96,1esting a -iinst the bolt-head (18. Thus as the ratchet-love and cam5.13 turn .iorwari'l togethcr as the unit moves from position P' to Ptheir relations are unchanged; but at the end of the outward shift thecam is stopped, and as the l'titt'tliOtdOVGl' rocks back the pin 89rides over the inclined lace oi the bolthead 98 and gradually forces thehead back deeper into the pocket as the pin is held out by thelooking-bolt Ti) ridiiig against lace T8; but as soon as theratchet-lever has rocked back to normal position the pin 89 is pushedback by the outer edge of the bolt J8 and the locki1'igdog Til is movedup into the notch 77', the outer end of the pin as then lying flush withthe side Face 01 the cam 93. During this for ard and return stroke ofthe ratchetlevcr the ioeking-dog is held down, but sweeps back and forthin an are 01 a circle, which movement is provided for by the concaveundercut face 78 in the coupling-bar '71. its the unit moves fromposition P" to i." and as the main shaft and cams turn in the forwardstroke the cam 93 depresses the roek-l(.-ver 1.03 and pushes up theoperating-rod 107, thereby rocking the shaft 1.16, tilting arm 115, andraising trip-ierer 116. The unit now stands in position 1 and as itmoves to position P the coupling-Mrs are shifted forward and back as onepiece, as they are con pled, and the ratchet and cams are turned a stepahead. accordingly; but the cam 93 still holdsthe trip-lever 116 up. Theunit now stands in position P", and as it moves to position il thecouplingdmrs are again shifted forward and back, and during the Forwardstroke the cam 93 moves otl' from the rocklever 103, thereby droppingthe trip-lever 1H3; 'lhe unit now stands in position P,

thus completing a cycle.

The relation oi the units to each other and to the train and theoperation 01 the system will now be described.

.lte't'erring to Figs. 21, 22, and 23, in the upper section of each oftl'iese l'igures there are litteen units re n-esented, the respectiveunits being designated 1 to 15, inclusive. large circle represents theratchet-wheel 21, while the respective cables are designated 1" to 15.25 designates the ratchet-lever of each unit. In Fig. 21 the nine cables3" to 11", inclusive, are coupled. The units 3, a, 5, 6, 7, S, 9, 10,and 11 are shown in their respective positions I I P, 1", P I P, P andP. The units 1, 2, 12, 13, 1 1, and 15 are respectively in positions PThe unit in position I?" has its rear cable uncoupled. Those units whichare in position P have their forward cable uncoupled from their rearcable, as has before been brought out in de scribing the operation of asingle unit. In the lower section of Fig. 21 the small open circlesrepresent trip-levers down, and the black circles represent trip-leversup. The short lines adjacent the circles represent the track-levers. Thelight lines represent the track-levers which are down and the heavylines represent the track-levers which are up. As before pointed out,when a unit is in position P its forward cable is uncoupled, itstrip-levers are down, and its track-lever is down. Hence units 1 and 2in the diagram which are in position P have their tracklevers andtrip-levers down and their forward cables uncoupled at the junction inthe units. Units 12, 13, 14, and 15 are likewise in the same condition.Unit 11 being in position P is protective, has its trip-lever 116" up,its track-lever down, and the cables 10 and 11" coupled in the unit. Theunit 10 being in position P is protective, has its trip-lever 116 up,its track-lcver down, and the cables 9 and 10 coupled in the unit. Unit9 being in position P is non-protective, has both its trip-levers down,its track-lever down, and the cables 8 and 9 coupled in the unit. Unit 8being in position P is non-protective, has both trip-levers down, itstrack-lever down, and the cables 7 and S coupled in the unit. Unit '7being in position P is non-protective, has its trip-levers both down,its track lever up, and the cables 6 and T coupled in the unit. Unit 6being in position I is nonprotective, has both of its trip-levers down,its track-lever down, and the cables 5" and 6" coupled in the unit. Unit5 being in position I is non-protective, has both of itstrip-leversdown, its track-levers down, and the cables 1 and 5 coupled in the unit.Unit t being in position P is protective, has its trip-lever 116 up, itstrack-lever down, and the cables 3 and r coupled in the unit. Unit 3being in position P is protective, has its trip-lever 116" up, itstrack-lever down, and cable 2 uncoupled in the unit and cable 3 coupledin the unit. The train is shown in position between units 6 and 7, andas it passes over unit 7 the chain of nine cables 3, r, 5, 6, 7", 8,

9 10 and 11 shifts forward and operates the ten units 3 to 12,inclusive, each through its respective step in its cycle.

Then this chain of cables and these units take the return stroke, at theconclusion of which the units are as represented in Fig. 23, the unit 3having been uncoupled and dropped from the chain and taking position Punit 13 having been brought into the chain by the connection of thecable 12" with the cable 11 at the unit 12. lllheintermediate units 4 to10, inclusive, remain coupled and each operated its respective step inits cycle. The train now lies between units 7 and S, and the zone ofprotection is advanced one point relatively to the track, but issubstantially the same with relation to the train, the unit 12 now beingan active unit and in protective condition presenting a raisedtrip-lever116, the unit 11 also being protective, presenting a raisedtrip-lever116". The unit 10 havinglowered its trip-lever isnon-protective. the unit 8 presenting a raised track-lever. The unit 3is inactive, having been dropped from the chain. Its trip-lever is down;but units a and 5 are both protective and present raised trip-levers116. In like manner the progression continues according to the speed ofthe train, so that the train is guarded both front and rear byprotective units which present raised triplevers.

In order to explain the shiftingof the chain of cables and consequentaction of the units connected therewith, reference is made to Figs. 18,19, and 20. These [igures are designed to embrace a series of elevenunits, four units having been removed, thusleaving units S, T, U, V, IV,X, and Y. This removal does not alter the action of the chain, as willbe seen. When a unit is in normal position with its ratchet-leverstanding back, its two springs 130 and 131 are both under an equaltension. In Fig. 18 units U to X are in position P to P, respectively,so that cables entering those units are all coupled. In the two extremeunits in this figure, S and Y, both of which stand in position P theforward cable of each of these units is uncoupled. Considering thecoupled cables B, C, D, E, and F as one continuous cable, which, infact, they form, there are live tension-springs 131 tending to pull thisunited cable to the left, and there are live tension-springs 130 tendingto pull the cable to the right. Thus the cable is balanced. It isimportant here to note that the two springs 130 and 131 of unit Ubalance each other, that the two tensionsprings of unit V balance eachother, that the tension-springs of unit IV balance each other, that thetension-springs of unit X balance each other, and that thetension-spring 130 of the unit Y balances the tension-spring 131 of theunit T. If new the tension-spring 131 of the unit V be slackened, (whichhappens when the train depresses the track-lever of that unit,) theeffect of that spring upon the chain is nullified, and hence there areonly four tension-springs 131 tending to pull the chain water to theleft as against live tension-springs 130 tending to pull the chain tothe right. Thus the chain of cables in its entirety shifts to the right./Vhile it may easily be understood that those machines which lie back ofunit V may be readily operated forward on account of the direct pull ofthe cables B C, it should be borne in mind that ahead of the unit V thethree springs 130 of units W X Y tend to pull the cables D E F forward,there being only the two springs 131 of units Vt and X which tend topull the chain to the left on account of the spring 131 of unit V havingbeen nulliiied. Hence that part of the chain which lies ahead of theunit V is over-balanced, and the three springs 130 of units W X Yovercome the two springs 131 of units W and X and pull the three cablesI), E, and F forward. In this connection it should be noted that thespring 131 of unit Y has no effect upon this action, as it does notenter into the chain at all, the unit Y being in position P and itsforward cable being uncoupled from the cable F. Observing the action ofthe units at the rearof the unit V it will be noted that as theratchet-lever of unit V moves forward cables 18 C are thus necessarilypositively drawn forward with it, placing the springs 1.31 of units T UV under a still greater tension and nullifying the two springs 130 ofunits U and V. The spring 130 of unit T does not enter into thiscombination as the ratchet-lever of unit T moves forward free from thecable A, the unit T being in position i with its rear cable uncoupled./Vhile as a matter of fact the foregoing the action which takes place inthe present embodiment of the invention, the rear cables B and C wouldmove forward without the direct tensile strain on those cables. Underthis arrangement of springs by reducing the tension of a spring of anyunit intermediate the units T and WV it will upset the balance of thechain and the chain will move accordingly, owing to the contraction ofthe majority of springs. it is apparent that as soon as the spring whichhas been nullified has had its tension restored the opposing strains areagain equalized and the chain will naturally shift back again. Thesprings i180 merely accelerate the return shift and obviously have noeffect on the chain when it is in normal position, inasmuch as at thattime the springs 1.30 and 131 both balance each other. The springs 180,while accelerating the return of the cable, are relatively weak and areemployed primarily for restoring the intermediate machine elements ineach unit and could be dispensed with, as they have no eflect upon thebalancing action of the cable.

Fig. .17 illustrates trip-lever protection for switches. Theverticalswitch-shaft 201 when turned opens or closes the switch by theusual mechanism, not necessary to describe, and it carries a disk 202.Pivotally connected to position P.

the disk at diametrically opposite points are cables 203 and 204;. Aseries of pivoted triplevers 205 are arranged at intervals along thetrack at one side of the switch and con-- nected to the cable 201-),while another series of tri -levers 5206 are arranginfl at intervals onthe other side of the switch and connected to the cable 20%. Vhen theswitch is operated, the shaft 20] turns the disk 202, which draws thecables 203 and 20% both toward the switch, thereby elevating thetrip-levers 205 and 206, as shown by dotted lines. When the switch isclosed, the trip-levers are low ered by the backward shift of thecables, which are restored by springs 20? and 208.

Fig. 2b IOIH'QHOilliH the switch closed with the trip-levers down. Fig.27 represents the switch open with the trip-levers up. Thus the switchwhen open is guarded by a series of triplevers on each side, and trainsapproachin from oitherd irection will be warned by the signal in the cabcaused by the outermost sentinel tripdevcrs and the trains will bebrought to a stop by the next trip-levels if the warning-signal is notheeded. Thus the trains cannot run past an open switch, but are free torun past a switch which is closed. While in this embodiment the unitwhich operates the chain is intermediate the terminals of the chain ofconnected units, other units than this could be utilized in thiscaptcity. in fact, any unit in the chain can be so employed by arrangingits track-lwer to be raised at the requisite cycle-point. This may bedone by simply adjusting the cam 102 on shaft 23. ,l'fdesired, the cam1H2 could be set to raise the track-lever when thcunit tool; ln thatcase there would be no head protection for the train; but such anarrangement might be desirable in certain systems. Obviously the camswhich operate the trip-lever may also be set to obtain other timing ofthe triplevers than as hereil'i shown, and, vice versa, the track-levercould be in operative condition when the unit was in position P. Thiswould give head protection to the train and no rear protection.

The employment of electric means in place of the shifting-cables forsecuring the harmonious cooperatiim of the units, which securesprogression of the protective zone, would not evade the scope of theclaims, as this construction of picking up new units and dropping offold units to cause a progression of the chain is ln-oadly new, and i donot limit myself to the employment of the specific means herein shownfor accomplishing the purpose. This progressive chain action requiresmuch less cable-line operating by tension or of wiring when electricmeans is employed for linking units than is required with independentoverlap iiing blocks, and it enables the concentration in a single unitof mechanism for accomplishing all functions.

More or less units could, be employed in the chain by increasing ordecreasing the number of teeth in the ratchet Qet accordingly.

It is apparent that the embodiment herein set forth is susceptible ofmany variations which would lie within the scope of the invention. Inthe claims the word train is used as including either a regular train ofengine and cars, an engine alone, a car alone, or, in fact, any vehicleoperating over the line.

WVhat I claim is 1. A plurality of distributed, normally-inactive unitssome of which being in a chain are active, one of the active units beingin protec tive condition and others in non-protective condition, andmeans operated by a train for dropping a unit from the chain and forchanging a unit in the chain from non-protective to protectivecondition.

2. A plurality of distributed, normally-inactive units some of whichbeing in a chain are active, some of the active units being inprotective condition and others in non-protective condition, and meansoperated by a train for linking an inactive unit into the chain and fordropping a unit from the chain and for changing a unit near the rear endof the chain into protective condition and changing a unit near thefront end of the chain into non-protective condition.

3. A plurality of distributed, normally-inactive protective units someof which being in a chain are active, and means controlled by a trainfor linking units into the chain and for dropping units from the chainas the train travels and for maintaining units at both ends of the chainin protective condition and maintaining intermediate units innon-protective condition.

4. A plurality of distributed, normally-inactive units each operative bysuccessive steps through a cycle, mechanism in each unit for renderingthe unit protective or non-protective according to its position of itscycle, and means controlled by a train for exercising simultaneously adefinite number of units through different cycle-steps.

5. A plurality of distributed, units a number of units adjacent thetrain being in a chain forming a protective zone and means operated by atrain for rendering protective a definite number of theactive units inthe zone back of the train and for linking other units with the chainand dropping units at the same rate from the chain to maintain the zoneof constant length.

6. A plurality of distributed units, a number of said units adjacent atrain being in a chain forming a protective zone, and means operated bythe train for linking other units with the chain and dropping units fromthe chain to maintain the zone adjacent the train as it travels.

7. A plurality of distributed units, a numtease? her of said units,adjacent a train being in a chain forming a protective zone in which thetrain is intermediate the limits thereof, and means operated by thetrain for linking units from without the chain into the chain andretiring units from the chain to maintain the zone in substantiallyconstant position relatively to the train as it'travels.

8. A plurality of distributed units, means operated by a train forrendering certain of the units protective, and means carried by a trainfor cooperating successively with protective units in the order of theirlocation along the track and signaling the latter train when inconjunction with the first-met protective unit.

9. A plurality of distributed units, means operated by a train forrendering certain of the units protective, and means carried by a trainfor cooperating successively with protective units in the order of theirlocation along the track and stopping the latter train when inconjunction with the second-met protective unit.

10. A plurality of distributed units, means operated by a train forrendering certain of the units protective, and means carried by a trainfor cooperating successively with protective units in the order of theirlocation along the track and operating a signal on the latter train whenin conjunction with the firstmet protective unit.

11. A plurality of distributed units, means operated by a train forrendering certain of the units protective, and means carried by a trainfor cooperating successively with protective units in the order of theirlocation along the track and setting the brakes on the latter train whenin conjunction with the second-met active unit.

12. A plurality of distributed units, means operated by a train forrendering certain of the units protective, and means carried by a trainfor cooperating successively with protective units for operatingasignalon the latter train when in conjunction with the firstmet protectiveunit, and for setting the brakes on the latter train when in conjunctionwith the second-met protective unit.

13. A plurality of distributed units, means operated by a train forrendering certain of the units protective, and means carried by a trainfor cooperating with a protective unit and first operating a signal onthe latter train, and for stopping the train when brought intoconjunction with another protective unit.

14. A plurality of distributed units, certain of the units being in achain forming a protective zone, means operated by a train for renderingcertain of the units in the zone protective, an electric circuit on atrain, and means on the latter train for cooperating with a protectiveunit controlling the electric circuit and means operated by the formertrain

